I want to note that the way the sex binary looks like it’s present throughout the animal world is that white scientists have a terrible habit of labeling everything “male” or “female” even when it makes no sense.
Like, by any reasonable metric, bees have three sexes: drone, queen, and worker. Workers are only labelled female because someone couldn’t abide the idea of something not being either one or the other.
And before someone calls “genetics” there are many species where both sexes have the exact same genetics, and even many where individuals can change reproductive capacity at will, and scientists suddenly have no problem calling the ones who grow eggs “female” even though they were “male” two weeks ago.
Some species of mammals reproduce asexually. They have only one sex. It is still called “female” because it makes babies even though one might reasonably ask why even make the distinction when every single individual makes babies just the same.